When one is overpowered by an intense,
almost sexual lust for all things historical.
This is often
manifested in the form of increased heart rate, ooh-ing, aah-ing, pointing or rapid photo taking, directed towards historical persons,
architecture or artifacts.
For those afflicted, historgasms can also result from any exposure, however limited, to any form of historical discussion or reference.
"I had a total historgasm last night thinking about
the mighty conquests of
Julius Caesar."
"Everytime I see a castle, man, my body just...historgasm man. Those turrets."
"I historgasm everytime Prof. Smith enters the lecture theatre, he's just so
passionate about his work."